Metallizing substrates

ABSTRACT

Substrates particularly thermoplastic resins and polymers, are plated with metals by pre-treatment of the substrate with a metallic coating by contacting said substrate with a basic solution of a metal salt to which is being introduced continuously or portionwise a phosphorus compound wherein the phosphorus has an oxidation number of less than 5. The resulting treated surface is conductive. Such conductive surfaces are readily electroplated by conventional techniques.

United States Patent Lin [451 Mar. 21, 1972 541 METALLIZING SUBSTRATES3,423,226 1/1969 Jensen ..117/47 3,438,805 4/1969 Potrafke ..l l7/l60[72] Inventor: Klngso Chingtsung Lin, Niagara Falls,

Primary Examiner-Ralph S. Kendall i Assistant Examiner-Jan ce A. Bell[73] Asslgnee' g s Ychemical Corporation Nlagara Attorney-Peter F.Caszlla, Donald C. Studley, James F.

a Mudd, Richard P. Mueller and William J. Crossetta [22) Filed: Aug. 6,1968 [57] ABSTRACT [2]] Appl. No.: 750,476

Substrates particularly thermoplastic resins and polymers, are platedwith metals by pre-treatment of the substrate with a U.S. 1 A, 1 R,metallic coating contacting said substrate a 0] 1 117/160, 1 tion of ametal salt to which is being introduced continuously [51] Int. CL...C23b 5/60, B44d U092 or ponionwige a phosphorus compound wherein the[58] Field of Search ..1 17/47, 47 R, 71, 160; 106/ l; phosphorus has anoxidation number of less than 5. The result- 204/30 1 ing treatedsurface is conductive. Such conductive surfaces 1 are readilyelectroplated by conventional techniques. [56] References Cited 16Claims, No Drawings METALLIZING SUBSTRATES BACKGROUND OF THE INVENTIONThere is a rapidly increasing demand for metal plated articles, forexample, in the production of low cost plastic articles that have asimulated metal appearance. Such articles are in demand in suchindustries as automotive, home appliance, radio and television and foruse in decorative containers and the like. Heretofore, the metal platingof plastics and the like has required many process steps, and generallysuch processes have been applicable to only one or a few relatedsubstrates.

It is an object of this invention to provide a simple process for themetal plating of plastics. Another object of the invention is to providea process that is applicable to the plating of many differentsubstrates, particularly the thermoplastic polymers. A further object ofthe invention is to provide articles having an adherent metal coatingthat is resistant to peeling, temperature cycling, and corrosion. Suchcoatings are electrically conductive whereby static charges are readilydissipated from the surfaces. The metal coatings further serve toprotect the articles from abrasion, scratching and marring, reduce theirporosity and improve their thermal conductivity. The process of thisinvention can be used for unidirectional mirrors and the like; water andliquid collecting devices and the like; protective coatings on houses,cars, boats, power line poles, street lights and the like; in thermalcontrol of clothing, houses and the like.

SUMMARY OF THE INVENTION This invention provides a process whichcomprises forming a metallic coating at the surface of a substrate torender the surface susceptible to conventional electroless platingand/or electrolytic plating.

More particularly, this invention provides a process which comprisesintimately contacting a substrate with a basic solution of a metal saltor complex thereof in the presence of a phosphorus compound wherein thephosphorus has an oxidation number of 3 or less. In one aspect of theinvention, the resultant surface is electroplated to deposit an adherentmetal coating on the surface. In another aspect of the invention, thetreated surface is subjected to electroless metal plating to deposit anelectroless conductive coating on the surface. Thereafter, the articlecan be electroplated so as to deposit an adherent metal coating of thedesired thickness on the electroless conductive coating.

Also in accordance with the invention, there is provided a articlehaving a metallic coating adherently formed at the surface of thesubstrate as a result of the process of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The process of this inventionis applicable to substrates, such as plastics and to other substantiallynon-metallic substrates. Suitable substrates include, but are notlimited to, cellulosic and ceramic materials such as cloth, paper, wood,cork, card board, clay, porcelain, leather, glass, asbestos cement, andthe like.

Typical plastics to which the process of this invention is applicableinclude the homopolymers and copolymers of ethylenically unsaturatedaliphatic, alicyclic and aromatic hydrocarbons such as polyethylene,polypropylene, polybutene, ethylenepropylene copolymers; copolymers ofethylene or propylene with other olefins, polybutadiene; polymers ofbutadiene, polyisoprene, both natural and synthetic, polystyrene andpolymers of pentene, hexene, heptene, octene, 2-methylpropene,4-methyl-hexene-l, bicyclo-(2.2.l )-2- heptene, pentadiene, hexadiene,2,3-dimethylbutadiene- 1,3,4-vinylcyclohexene, cyclopentadiene,methylstyrene, and the like. Other polymers useful in the inventioninclude polyindene, indenecoumaroneresins; polymers of acrylate estersand polymers of methacrylate esters, acrylate and methacrylate resinssuch as ethyl acrylate, n-butyl methacrylate, isobutyl methacrylate,ethyl methacrylate and methyl methacrylate; alkyd resins; cellulosederivatives such as cellulose acetate, cellulose acetate butyrate,cellulose nitrate, ethyl cellulose, hydroxyethyl cellulose, methylcellulose and sodium carboxymethyl cellulose; epoxy resins; furan resins(furt'uryl alcohol or furfuralketone); hydrocarbon resins frompetroleum; isobutylene resins (polyisobutylene); isocyanate resins(polyurethanes); melamine resins such as melamine-formaldehyde andmelamine-urea-formaldehyde; oleo-resins; phenolic resins such asphenol-formaldehyde, phenolicelastomer, phenolic-epoxy,phenolic-polyamide, and phenolic-vinyl acetals; polyamide polymers, suchas polyamides, polyamide-epoxy and particularly long chain syntheticpolymeric amides containing recurring carbonamide groups as an integralpart of the main polymer chain; polyester resins such as unsaturatedpolyesters of dibasic acids and dihydroxy compounds, and polyesterelastomer and resorcinol resins such as resorcinol-formaldehyde,resorcinol-furfural, resorcinol-pheonl-formaldehyde,resorcinal-polyamide and resorcina'l-urea; rubbers such as naturalrubber, synthetic polyisoprene, reclaimed rubber, chlorinated rubber,polybutaidene, cyclized rubber, butadiene-acrylonitrile rubber,butadiene-styrene rubber, and butyl rubber; neoprene rubber(polychloroprene); polysulfides (Thiokol); terpene resins; urea resins;vinyl resins such as polymers of vinyl acetal, vinyl acetate or vinylalcohol-acetate copolymer, vinyl alcohol, vinyl chloride, vinyl butyral,vinyl chloride-acetate copolymer, vinyl pyrrolidone and vinylidenechloride copolymer; polyformaldehyde; polyphenylene oxide; polymers ofdiallyl phthalates and phthalates; polycarbonates of phosgene orthiophosgene and dihydroxy compounds such as bisphenols, thermoplasticpolymers of bisphenols and epichlorohydrin (tradenamed Phenoxypolymers); graft copolymers and polymers of unsaturated hydrocarbon andan unsaturated monomer, such as graft copolymers of polybutadiene,styrene and acrylonitrile, commonly called ABS resins; ABS-polyvinylchloride polymers, recently introduced under the tradename of Cycovin;acrylic polyvinyl chloride polymers, known by the tradename of KydexI00; polytetrafluoroethylene and poly(monochlorotrisfluoroethylene).

The polymers of the invention can be used in the unfilled condition, orwith fillers such as glass fiber, glass powder, glass beads, asbestos,talc andother mineral fillers, wood flour and other vegetable fillers,carbon in its various forms, dyes, pigments, waxes and the like. If awax is used as a filler, it has been found that the harder the wax, themore adherent the metal will be bound to the substrate.

The substrates of the invention can be in various physical forms, suchas shaped articles, for example, moldings, sheets, rods, beads, and thelike; fibers, films and fabrics, and the like.

As a result of the treatment step of the invention, a metallic coatingis deposited at the surface of the substrate. The metallic coating isprimarily elemental metal but can also include phosphorus from thephosphorus in the reducing agent. Without being limited to theory, themetal-phosphorus portion of the coating can be an alloy or compound.

In the treatment step of the process of the invention, the substrate iscontacted with a solution of a metal salt or a complex of a metal salt,which is capable of being reduced by a phosphorus compound of theinvention to form a metallic coating. The metals generally employed arethose of Groups IB, IIB, IVB, VB, VIB, VIIB and VIII of the PeriodicTable appearing on pages 60-61 of Langes Handbook of Chemistry (RevisedTenth Edition). The preferred metals are copper, silver, gold, chromium,manganese, cobalt, nickel; palladium, titanium, zirconium, vanadium,tantalum, cadmium, tungsten, molybdenum, and the like.

The metal salts that are used in the invention can contain a widevariety of anions. Suitable anions include the anions of mineral acidssuch as sulfate, chloride, bromide, iodide, fluoride, nitrate,phosphate, chlorate, perchlorate, borate, carbonate, cyanide, and thelike. Also useful are the anions of organic acids such as formate,acetate, citrate, butyrate, valerate, caproate, heptylate, caprylate,naphthenate, 2-ethyl caproate, cinnamate, stearate, oleate, palmitate,dimethylglyoxime, and the like. Generally the anions of organic acidscontain one to 18 carbon atoms.

Some useful metal salts include copper sulfate, copper chloride, silvernitrate and nickel cyanide.

The metal salts can be complexed with a complexing agent 5 that producesa solution having a basic pH 7). Particularly useful are the ammoniacalcomplexes of the metal salts, in which one to six ammonia molecules arecomplexed with the foregoing metal salts. Typical examples include NiSO'6NH NiCl,*6NH Ni(C H OO) *6NH CuSO -6NH CuCl '6NH AgNO -NH NiSO -3NHCuSO,'4NH Ni(NO -4Nl-l and the like. Other useful complexing agentsinclude quinoline, amines and pyridine. Useful complexes includecompounds of the formula MX Q wherein M is the metal ion, X is chlorineor bromine and Q is quinoline. Typical examples include: CoCl Q CoBr Q,,NiCl Q NiBr Q Nil Q MnCl Q CuCl Q CuBr Q- and ZnCl Q Also useful are thecorresponding monoquinoline complexes such as CoCl Q. Useful aminecomplexes include the mono-(ethylenediamine)-, bis- (ethylenediamine)-,tris-(ethylenediamine)-, bis-(1,2-propane diamine)-, and bis-(l,3-propanediamine)- complexes of salts such as copper sulfate. Typicalpyridine complexes include NiCl (py), and CuCl (py) where py ispyridine.

The foregoing metal salts and their complexes are used in ionic media,preferably in aqueous solutions. However, nonaqueous media can beemployed such as alcohols, for example, methyl alcohol, ethyl alcohol,butyl alcohol, heptyl alcohol, decyl alcohol, and the like. Mixtures ofalcohol and water can be used. Also, useful are ionic mixtures ofalcohol with other miscible solvents of the types disclosedhereinbefore. The solution concentration is generally in the range fromabout 0.1 weight percent metal salt or complex based on the total weightof the solution up to a saturated solution, preferably from about 1 toabout 10 weight percent metal salt or complex. The pH of the metal saltor complex solution is generally maintained in the basic range, i.e.,greater than 7, and preferably from about 10 to about 13.

The step of contacting the substrate with the solution of metal salt isgenerally conducted at a temperature below the softening point of thesubstrate, and below the boiling point of the solvent, if one is used.Generally the temperature is in the range of about to 110 centigrade,preferably from about 25-l0ObL centigrade. The time of contact can varyconsiderably, depending on the nature of the substrate, thecharacteristics of the metal salts employed and the contact temperature.However, the time of contact is generally in the range of about 0.1 to30 minutes, preferably about 1 to minutes.

The metallic coating is applied to the surface of the substrate byintroducing a phosphorus component continuously or portionwise into themetal salt solution while the substrate is in contact therewith. Themetallic species generated by the reaction of the phosphorus compoundand the metal cations have a strong tendency to adhere to the substratesurface. This tendency is enhanced when the metal in its nascent form israpidly brought into intimate contact with the substrate. Thecoincidental reduction of the metal and its impingement on the substratecan be effected by suitable agitation. For example, the substrate can beplaced in a flowing stream composed of the metal salt solution, intowhich the phosphorous compound is passed. The phosphorus compound can beejected from a nozzle against a substrate suspended in a rapidly stirredmetal salt solution. Suitable phosphorus compounds or phosphoruscomponents are those wherein the phosphorus has low oxidation; thephosphorus has an oxidation number of less than 5, more particularly theoxidation number can be 3, -2, 0, l or +3.

Typical phosphorus compounds that can be employed are phosphine,diphosphine, hypophosphorous acid and the salts thereof of the metals ofGroups I, ll and 111A; phosphorous acid and the salts thereof of themetals of Groups I, ll and lIlA; and the phosphides of the metals ofGroups IA, HA, and "IA. The preferred salts of the acids include thesodium, potassium and lithium salts. The preferred phosphides arecalcium and aluminum phosphides. Less preferred are the compounds ofcopper, magnesium, calcium, strontium, cesium, zinc, cadmium, aluminumand gallium. Particles of elemental phosphorus can be used.

As a result of the treatment step of the invention, a metallic coatingis deposited at the surface of the substrate. The metallic coating isprimarily elemental metal but can also include phosphorus from thephosphorus in the reducing agent. Without being limited to theory, themetal-phosphorus portion of the coating can be an alloy or compound.

Following the foregoing treatment step, the substrate can be rinsed withwater or a solvent, and then can be dried by merely exposing thesubstrate to the atmosphere or to inert atmospheres such as nitrogen,carbon dioxide, and the like, or

by drying the surface with radiant heaters or in a conventional oven.Drying times can vary considerably, for example, from I second to 30minutes, or more, preferably 5 seconds to [0 minutes, more preferably 5to 120 seconds. The rinsing and drying steps are optional.

The treated substrates that result from the foregoing process can besubjected to a process that has become known in the art as electrolessplating or chemical plating. In a typical electroless plating process, acatalytic or metallic surface is contacted with a solution of a metalsalt under conditions in which the metallic ion of the metal salt isreduced to the metallic state and deposited on the catalytic or metallicsurface. The use of this process with the products of this inventionrelies upon the electroconductive coating deposited on the surface as aresult of the treatment with the solution of metal salt or complex andphosphorus compound of this invention. A suitable chemical treating bathfor the deposition of a nickel coating on the electroconductive surfaceproduced in accordance with the process of the invention can comprise,for example, a solution of a nickel salt in an aqueous hypophosphitesolution. Suitable hypophosphites include the alkali metal hypophosphitesuch as sodium hypophosphite and potassium hypophosphite, and thealkaline earth ,metal hypophosphites such as calcium hypophosphite andbarium hypophosphite. Other suitable metal salts for use in the chemicaltreating bath include the metal salts described hereinbefore withrespect to the metal salt treatment of the phosphorus-treated substrateof the invention. Other reducing media include formaldehyde,hydroquinone and hydrazine. Other agents, such as buffering agents,complexing agents, and other additives are included in the chemicalplating solutions or baths.

The treated substrates of the invention can be electroplated by theprocesses known in the art. The article is generally used as thecathode. The metal desired to be plated is generally dissolved in anaqueous plating bath, although other media can be employed. Generally, asoluble metal anode of the metal to be plated can be employed. In someinstances, however, a carbon anode or other inert anode is used.Suitable metals, solutions and condition for electroplating aredescribed in Metal Finishing Guidebook Directory for 1967, published byMetals and Plastics Publications, Inc., Westwood, NJ.

The following examples serve to illustrate the invention but are notintended to limit it. Unless specified otherwise in this specificationand claims, all temperatures are in degrees centigrade and parts areunderstood to be expressed in parts by weight.

EXAMPLE 1 (a) A solution was prepared by mixing grams of NiCl -6H 0,1,800 milliliters of water and 600 milliliters of concentrated ammoniumhydroxide (28-30 percent NH Phosphine was introduced to the solution ata rate of 0.79 grams per minute, while vigorously agitating thesolution. A plastic article comprised of a graft copolymer ofpolybutadiene, styrene and acrylonitrile was introduced into thevigorously agitated solution, which was at a temperature of 26-27centigrade,

for a total period of 2 minutes, 25 seconds. A portion of the plasticarticle had been abraded with steel wool, the remainder of the plasticarticle had been treated with concentrated nitric acid for 2 minutes. Atthe end of the treatment, it was observed that an adherent conductivemetal surface had been formed on both portions of the plastic article.

Another ABS copolymer article was abraded with steel wool and treated inaccordance with the above-described process of the invention. As aresult, an adherent metal conductive surface was formed on the plasticsurface.

Still another ABS copolymer article was contacted with concentratednitric acid for one minute and thereafter subjected to the process ofthe above-described process. Again, an adherent metallic conductivesurface was'formed on the surface of the plastic article.

The above-described metal coated articles were then subjected to aMacDermid electroless nickel plating bath whereby an electroless nickeladherent coating was applied to the surfaces of the plastic articles.The thus treated articles were then copper plated in a Udylite brightacid copper plating bath at a current density of 40 amperes per squarefoot to produce and adherent copper plate on the outer surface of theplastic articles.

The foregoing process is repeated utilizing other ammoniacal metal saltsas follows to form metallic coating on the surface of ABS articles.

b. nickel sulfate c. copper chloride d. silver nitrate e. cobaltchloride f. nickel acetate EXAMPLE 2 A solution was prepared by mixinggrams of NiCl -6H O, 100 milliliters of concentrated ammonium hydroxide28-3 0% Mi and 300 milliliters of water. The resulting solution wasvigorously agitated at about 30 centigrade in a glass container.Thereafter, phosphine was introduced to the solution and a metalliccoating was deposited on the inside surface of the glass container. Theforegoing process was repeated in a polyethylene container, and theinside surface of the polyethylene container was similarly metal coated.Both containers were emptied and dried and the metallic coatings formedon the inside surface of the container were tested for conductivity byapplying a pair of electrodes to the metallic surfaces. The electrodeswere spaced 0.75 centimeters apart.

The metal coated glass surface exhibited a resistance of 33 ohms, whilethe metal coated polypropylene surface was found to have a resistance ofabout 200 ohms.

EXAMPLE 3 The process of Example I was repeated at several temperaturesutilizing a polytetrafluoroethylene substrate. The temperature andphosphine rate was varied as follows:

Phosphine Rate Polymer Sample Temperature Grams Per Minute A 25 0.66 B39 0.88 C 4 0.5

In all cases, the polymer samples were nickel-coated, and the samplethat had been treated at 25 centigrade had the most adherent metalliccoating.

EXAMPLE 4 was vigorously agitated. Various substrates were subjected totreatment in the metal salt bath as follows.

a. A polypropylene article that had been washed with a detergent,acetone and water and dried, was introduced into the coating bath for159 seconds at 26-27 centigrade at an agitator speed of 5,095revolutions per minute. The resulting treated polypropylene surface wastested and found to have a conductive metal coating adherently depositedthereon.

b. An article made from ABS (graft copolymer of polybutadiene, styreneand acrylonitrile) was subjected to the abovedescribed metal coatingbath for 2 minutes, 18 seconds at 2526 centigrade, while being agitatedat 5,635 revolutions per minute. The resulting treated article was foundto have a homogeneous, metallic coating that was conductive.

The above-described process is applied to the following additionalsubstrates to deposit conductive metallic coatings on the surfaces ofthe substrates.

c. Phenol-formaldehyde novolac resin.

d. Polyethylene terephthalate.

e. Glass plate.

f. Wood.

g. Porcelain.

h. Cork.

i. Asbestos cement.

The process of the invention can be conducted by introducing elementalphosphorus, particularly white or yellow phosphorus into the metal saltbath instead of the phosphine of the foregoing examples. Finely dividedphosphorus particles are introduced to the aqueous solution andphosphine is formed in situ to provide the low oxidation statephosphorus compound.

Various changes and modifications can be made in the process andproducts of this invention without departing from the spirit and scopeof the invention. The various embodiments of the invention disclosedherein serve to further illustrate the invention but are not intended tolimit it.

1 claim:

1. A process which comprises forming a metallic coating at the surfaceof a substantially non-metallic substrate by intimately contacting thesubstrate with a basic, aqueous solution of a metal salt or complexthereof in the presence of a phosphorus compound wherein the phosphorushas an oxidation number of less than 5; wherein the metal is selectedfrom groups 1B, 118, lVB, VB, VIB, VlIB and Vlll of the periodic table.

2. A process which comprises forming a metallic coating at the surfaceof a substantially non-metallic substrate by intimately contacting thesubstrate with a basic, aqueous solution of a metal salt or complexthereof, which solution also contains a phosphorus compound wherein thephosphorus has an oxidation number of less than 5, wherein the metal isselected from groups 13, llB, lVB, VB, VlB, VIIB and Vlll of theperiodic table.

3. A process which comprises forming a metallic coating at the surfaceof a substantially non-metallic substrate by contacting the substratewith a basic, aqueous solution of a metal salt or complex thereof, andsimultaneously agitating the solution and introducing thereincontinuously or portionwise a phosphorus component, wherein the metal isselected from groups IB, llB, IVB, VB, VIB, VllB and VIII of theperiodic table, and wherein the phosphorus component is selected fromthe group consisting of elemental phosphorus, phosphine, diphosphine,hypophosphorous acid and the salts thereof of the metals of groups I, IIand "IA, phosphorous acid and the salts thereof of the metals of groupsI, II and IIIA, and the phosphides of the metals of groups 1A, 11A and111A.

4. The process of claim 3 wherein the phosphorus component is phosphine.

5. The process of claim 3 wherein the phosphorus component is sodiumhypophosphite.

6. The process of claim 3 wherein the metal salt complex is anammoniacal complex of a nickel salt.

7. The precess of claim 6 wherein the nickel salt is nickel chloride.

Z W a. 8. The precess wherein the treated substrate resulting from 12.The process of claim 3 wherein the substrate is the process of claim 1is subjected to electroless metal plating l ylen to deposit anelectroless conductive coating on the treated 13 The process f claim 3wherein h Substrate is a graft Substratecopolymer ofpolybutadiene,styrene and acrylonitrile.

9. A process wherein the substrate resulting from the 5 process of claim8 is electroplated to deposit an adherent metal coating on theelectroless conductive coating.

10. A process wherein the treated substrate resulting from the processof claim 1 is electroplated to deposit an adherent metal coating on thetreated substrate. l0

11. The precess ofclaim 1 wherein the substrate is a plastic.

14. The process of claim 3 wherein the substrate is a polycarbonate.

15. The process of claim 3 wherein the substrate ispolytetrafluoroethylene.

16. The process of claim 3 wherein the substrate is glass.

UNITED STATES PATENT OFFEQE CERTIFFCATE OF CORREC'NGN 2atent No.3,650,911 D d March 2] I972 Inventor) Kingso Chingtsung Lin It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

1'- Column 3, line +3, 100bL" should read 100 *g Column 6, line 7"precess" should read process Column 7, line I I "process" should readprocess si ned and sealed this 18th day of July 1972.

(SEAL) Attest:

EDWARD M.FLETGHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissionerof Patents

2. A process which comprises forming a metallic coating at the surfaceof a substantially non-metallic substrate by intimately contacting thesubstrate with a basic, aqueous solution of a metal salt or complexthereof, which solution also contains a phosphorus compound wherein thephosphorus has an oxidation number of less than 5, wherein the metal isselected from groups IB, IIB, IVB, VB, VIB, VIIB and VIII of theperiodic table.
 3. A process which comprises forming a metallic coatingat the surface of a substantially non-metallic substrate by contactingthe substrate with a basic, aqueous solution of a metal salt or complexthereof, and simultaneously agitating the solution and introducingtherein continuously or portionwise a phosphorus component, wherein themetal is selected from groups IB, IIB, IVB, VB, VIB, VIIB and VIII ofthe periodic table, and wherein the phosphorus component is selectedfrom the group consisting of elemental phosphorus, phosphine,diphosphine, hypophosphorous acid and the salts thereof of the metals ofgroups I, II and IIIA, phosphorous acid and the salts thereof of themetals of groups I, II and IIIA, and the phosphides of the metals ofgroups IA, IIA and IIIA.
 4. The process of claim 3 wherein thephosphorus component is phosphine.
 5. The process of claim 3 wherein thephosphorus component is sodium hypophosphite.
 6. The process of claim 3wherein the metal salt complex is an ammoniacal complex of a nickelsalt.
 7. The precess of claim 6 wherein the nickel salt is nickelchloride.
 8. The precess wherein the treated substrate resulting fromthe process of claim 1 is subjected to electroless metal plating todeposit an electroless conductive coating on the treated substrate.
 9. Aprocess wherein the substrate resulting from the process of claim 8 iselectroplated to deposit an adherent metal coating on the electrolessconductive coating.
 10. A process wherein the treated substrateresulting from the process of claim 1 is electroplated to deposit anadherent metal coating on the treated substrate.
 11. The precess ofclaim 1 wherein the substrate is a plastic.
 12. The process of claim 3wherein the substrate is polypropylene.
 13. The process of claim 3wherein the substrate is a graft copolymer of polybutadiene, styrene andacrylonitrile.
 14. The process of claim 3 wherein the substrate is apolycarbonate.
 15. The process of claim 3 wherein the substrate ispolytetrafluoroethylene.
 16. The process of claim 3 wherein thesubstrate is glass.